Hardboard structure



Oct. 23, 1956 E. R. SCZES'NY 2,767,512

' HARDBOARD STRUCTURE Filed Sept. 21, 1955 E. RSCZ ESNY INVENTOR.

By 1 m ATTORNEYS United States Patent HARDBOARD STRUCTURE Edward R. Sczesny, Inkster, Mich, assignor to Ford Motor Company, Dearborn, Mich, a corporation of Delaware Application September 21, 1955, Serial No. 535,678

4 Claims. (Cl. 45-138) This invention relates to the field of pressed cellulosic products and specifically to a hardboard structure suitable for use in fabricating automotive bodies.

in fabricating automobile body components and specifically automobile doors, it is conventional to provide the decorative fabric interior with a supporting layer of paper hardbo'ard to support the decorative fabric in the proper position with relation to the remainder of the door. Difficulty has been encountered with structures of this type due to the inherent instability of conventional hardboards when repeatedly wetted and dried. This is particularly true with the lower portion of the car door where the hardboard supporting layer is frequently wetted and dried from rain leaking around the window seal and from overly enthusiastic car washing. These repeated wettings cause warpage of the hardboard with concomitant wrinkling of the supported fabric.

This invention has been developed especially to produce a hardboard structure which is relatively immune to the eifects of repeated wetting and drying. The structure of this paper board is best understood by reference to the drawings in which:

Figure l is an elevation view of a sheet of hardboard now fabricated on a commercial scale for lining motor vehicle doors, and,

Figure 2 is w enlarged view of the portion of the hardwood sheet encircled in Figure l.

The hardwood board with which this invention is concerned comprises macerated paper, aluminum sulfate and Vinsol resin. Vinsol resin is a commercially accepted product, naturally occurring in pine stumps and characterized by its insolubility in straight chain hydrocarbons. For a more specific definition of this material, reference is had to the Condensed Chemical Dictionary, third edition, 1942, published by the Reinhold Publishing Company, on page 662. A normal resin content of this paper is from to 20 percent with an average content of percent conventionally. This hardboard is fabricated by producing a wet sheet and placing the wet sheet in steamheated presses between wire platens. The fabrication of such material is conventional and forms no part of this invention.

In Figure 1, edge 12 represents the lower edge of the sheet as applied to the door. It is this edge, of course, which is most seriously affected by moisture. It has been discovered that the provision of a series of elongated,

open-ended slots 10 and oval openings 11 along the bottom edge 12 of the sheet has for all practical purposes completely overcome the difiiculties which are encountered in conventional structures due to wetting. Oval openings 11 may be omitted if the maximum benefit is not required. However, the presence of elongated, openended slots 10 is necessary if warpage is to be avoided. Boards constructed in accordance with this invention have been repeatedly wet and dried with no visible warpage.

Figure 2 is an enlarged view of the area of the hardboard encircled in Figure 1. This figure of drawing shows more clearly the elongated, open-ended slots 10 and oval openings 11. The unnumbered round and rectangular openings seen in both Figure l and Figure 2 are provided for the reception of trim fasteners.

It is to be understood that the exact construction and number of slots 10 may be varied without departing from the spirit of the invention as long as these slots are open to bottom edge 12 and are relatively long with reference to their width.

I claim as my invention:

1. A sheet of hardboard for supporting fabric in automotive body construction comprising macerated paper, aluminum sulfate and Vinsol resin, one edge of said sheet being characterized by the presence of open-ended slots extending from said edge into the interior area of said sheet, said slots being relatively long as compared to their width.

2. A sheet of h'ardboard for supporting fabric is automotive door construction comprising macerated paper, aluminum sulfate and Vinsol resin, the edge of said sheet which conforms to the door bottom being characterized by the presence of open-ended slots extending from said edge into the interior of said sheet, said slots being relatively long as compared to their width.

3. A sheet of hardboard for supporting fabric in automotive door construction comprising macerated paper, aluminum sulfate and from ten to twenty percent Vinsol resin, the edge of said sheet which conforms to the door bottom being characterized by the presence of open-ended slots extending from said edge into the interior of said sheet, said slots being relatively long as compared to their width.

4. A sheet of hardboard for supporting fabric in automotive door construction comprising macerated paper, aluminum sulfate and from ten to twenty percent Vinsol resin, the edge of said sheet which conforms to the door bottom being characterized by the presence of open-ended slots extending from said edge into the interior of said sheet, said slots being relatively long as compared to their width and said sheet being further characterized by the presence of oval openings near such edge.

References Cited in the file of this patent UNITED STATES PATENTS 2,058,622 Place Oct. 27, 1936 2,160,636 Ball May 30, 1939 2,539,956 Klingensmith Jan. 30, 1951 

